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After 2 or maybe 3 years with an 12 inch Meade SCT I started to wonder what I was thinking :) Most certainly it was aperture fever, but I did not find the scope to excel at anything. Visually the views are average, DSO imaging is a pain with mirror shift, focusing by moving the mirror..etc. The only thing we use SCTs are planetary imaging?

Why did you guys get an SCT? And what are you using it for? Are you happy with it? 

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After attending a star party 24 years ago and looking through most telescope types, I determined that the Dobsonian Newtonian was the best starter scope for me.  As I recall, I was most unimpressed with SCT views as being soft in comparison to those of Newts.  APO refractors simply lacked aperture to compete with the big Dobs.  I don't think there were any Maks on the field.

It's funny that everything you describe about SCTs from your experience correlates very well with that single night of "comparison shopping" I did so long ago.

I am thinking about getting a 6" or 8" SCT just see if things have improved any over the last 24 years.  I was super impressed with the views of Jupiter through an 8" EdgeHD a couple of years back at a star party, so it got me to thinking they might be worth another look.

Edited by Louis D
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My first SCT was a Celestron C11 XLT Carbon, which I primarily bought for planetary imaging. Reasons why I bought it were lack of spider (= no spikes, but in planetary imaging that seems to be marginal), aperture (= more detail) and focal length (=more magnification). Excessive mirror-flop and better optics made me decide to swap it for a C11 XLT EdgeHD as that scope has mirror-lock. It was at that point that I found out there is mirror-shift (play between the baffle-tube and mirror-tube) and mirror-flop (loose mounting of the mirror on the outer tube). Mirror-shift is something I can live with as it is only 30" at maximum (factory specs, mine has about 24"). Mirror-shift causes the scope to go out of collimation, so requires re-collimation as soon as the imaging session is interrupted by the meridian-flip. I returned the scope to Celestron for repair, but despite their promise they did not manage to repair it and did not even seem to bother (see my article on a Dutch forum, opening it in Chrome will translate it for you).

Hopefully this year I will have it properly repaired. I anticipate that if that repair is successful I will have a great scope!

As stated above I use the scope mainly for planetary imaging, but also for visual observing of planets and DSOs using TeleVue Ethos and Panoptic eyepieces (M13 is just great through it!).

Nicolàs

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I got a C11 for CCD photometry of variable stars. Very happy with it. Lots of aperture for stars down to mag 19. It’s operating in the obsy right now.

Also have a C9.25 as a more portable setup for taking to dark sky sites and public outreach. Enough aperture to show lots of object types well. VisualLy.

But I’m really a refractor man at heart, so I farm a few of those as well 😊

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I think a lot of people buy SCT's because they see a lot of them in use, often within societies. Within the astro society that I belonged to most of the members who had scopes had SCT's. Personally, I've owned a few SCT's up to 8 inches and observed with them up to 14 inches in aperture. I've not been overwhelmed by the views from them generally speaking. I don't image though, just a visual observer.

Happy to stick to newtonians on dobsonian mounts and refractors over the past few years.

I'm sure the SCT has it's place in the hobby for good reasons though. I know quite a few of our members in this forum have been very happy with theirs. I'm sure they will be "chiming in" soon :smiley:

 

Edited by John
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I swapped mm Mak180 for a SCT C9.25, because i wanted a bit more versatility with my scope. The slightly shorter focal length and abilty to use a reducer have certainly given me this. Planetary imaging wise, which is what i do most, i am not sure there is a huge difference in the two scopes.

Visually i have enjoyed using on a variety of objects, its big, but pretty managable (at the moment)

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i had a mak 150 then a c6 and thought they were good. a few years later sold them and bought a cpc 9.25 an loved it, untill i bought a dob. the views in the little dob just blew it out of the water

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I bought a C9.25 to replace a 250mm Newt. Just because the 250mm was too bulky for me to lift. Views were sharp, but never as much contrast; very noticeable on Jupiter.

Brought home more now as I'm using a 150mm Rumak which is showing more detail on Mars at 10" than the C9.25 ever did. The 150mm is more prone to bringing out floaters though.

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I wanted a reasonable all-round visual scope, with potential for planetary imaging, and the ability to transport it easily in a small car. The Celestron GP-C8 fit the bill neatly, 25 years ago. It now has some company, with the acquisition of first an APM 80mm F/6 triplet for wide-field observing and DSO and solar imaging, an EQ3-2 mount, a GP-DX mount, and a Meade SN6 6"F/5 Schmidt-Newton for DSO imaging and visual comet hunting. The GP-C8 is still the main scope for visual, and certainyl for planetary and lunar imaging.

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1 hour ago, Louis D said:

After attending a star party 24 years ago and looking through most telescope types, I determined that the Dobsonian Newtonian was the best starter scope for me.  As I recall, I was most unimpressed with SCT views as being soft in comparison to those of Newts.  APO refractors simply lacked aperture to compete with the big Dobs.  I don't think there were any Maks on the field.

It's funny that everything you describe about SCTs from your experience correlates very well with that single night of "comparison shopping" I did so long ago.

I am thinking about getting a 6" or 8" SCT just see if things have improved any over the last 24 years.  I was super impressed with the views of Jupiter through an 8" EdgeHD a couple of years back at a star party, so it got me to thinking they might be worth another look.

For a while in college I had an 10 inch DOB. That scope impressed me almost every night. Glad to see others had similar experiences!

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51 minutes ago, JeremyS said:

I got a C11 for CCD photometry of variable stars. Very happy with it. Lots of aperture for stars down to mag 19. It’s operating in the obsy right now.

Also have a C9.25 as a more portable setup for taking to dark sky sites and public outreach. Enough aperture to show lots of object types well. VisualLy.

But I’m really a refractor man at heart, so I farm a few of those as well 😊

CCD photometry could be a solid reason for the SCT. Did you find mirror shift/flop to be an issue in photometry? I'm guessing with shorter exposures the impact will not be important?

I have to say, the SCT drove me in the hands of a big refractor, and I might become a refractor man for life, if only the clouds will go away

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I have used sct's, refractors, maksutovs, and Newtonians.

I have a C8 and as has been said the views are softer than the other types deliver.

My C8 has been the least used of my scopes partly for this reason.

To be fair it can do a lot but it isn't inspiring.

It's likely to stay with me as it fills a gap nicely between a small refractor and a big dobsonian but whereas taking those out is exciting, taking the C8 out doesn't result in the same feeling.

Oddly though if I'm going away from home to a meet up the C8 is often the choice as it's the most aperture I can fit in my car currently.

To keep my post balanced I'd add that I did once get a shockingly good view of M42 with the C8 and it does beat my smaller scopes for lunar detail even though the view is softer.

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I've used and owned Refractors, Maks, SCT (just one, an 8") and Newtonian ( a couple).

It's no coincidence that in order of preference, to me personally, they run in the same order..

I really love Refractors..I like the way they look, I love the sharp images and contrast they deliver, I like their ease of use, and their low maintenance requirements.

I really like Maksutovs (especially Russian ones), the good ones get very close to refractor performance, they hold collimation well, and I like their looks and compact size/low maintenance. I don't like their long cools down times.

I am not a big fan of Newtonians, but that's just me..I don't like viewing down into the side of the tube with my neck slanted. I don't like the thought of having to collimate them regularly, and I don't fancy lugging them about when they are 8" or bigger.

But I accept fully that they offer the best value for money, best aperture for deep sky, and, in specialist form such as those by Zambuto, excellent planetary performance. They are perhaps the ideal scope for a beginner to start with. I must just give an honourable mention to the diminutive TAL Alcor 3" reflector..built like a tank, superbly sharp optics and a mount you could probably put a 10" Newt on!

Finally, I really don't like SCTs (optically I freely admit based on one short and very unimpressive ownership).. the one I had (Celestron) felt cheaply built, and was very mushy in it's views. Maybe I got a dud, but it put me off for life, sorry.

There, that's what I think..

Shields Up, Mr Worf!! 😁😂

Dave

 

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I dont think that they have invented a scope yet that isn't a series of compromises.. 

Refactors get very heavy with size meaning very expensive mounts for the realy big ones..

Maks are probably closest to refractor performance and easy to mount but size is limited and comes with the dreaded cool down.

Newts are biggest bang for the buck but get unwieldy with size and of course those dreaded spikes.

SCT scopes overcome some of the size limitations and cool down issues as well as being easier to mount but is it a case of one compromise too many?

The new breed of classical cassegrains and similar designs that are very popular at the moment that look to be a threat to all the other types.

Alan

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46 minutes ago, dan_adi said:

CCD photometry could be a solid reason for the SCT. Did you find mirror shift/flop to be an issue in photometry? I'm guessing with shorter exposures the impact will not be important?

I have to say, the SCT drove me in the hands of a big refractor, and I might become a refractor man for life, if only the clouds will go away

No mirror shift issues as I have add an after market focuser. The scope gets flipped across the sky and never any mirror flip. Only issue is the tube expands or contracts with temperature changes, so refocusing is required during the night.

For photometry, the more photons the better, so bigger aperture.

But nothing like using my Takahashi TSA 120 😊

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I got my Celestron C6/SCT-xlt soon after a mishap/an accident with my Meade ETX105 as a replacement for it, as I was looking for a replacement ETX rear cell to replace the damaged one. Unable to get one from Meade or secondhand. A few years elapsed and I drew up a sketch/plan and asked a few local engineering workshops to fabricate a replacement backplate from aluminium. Luckily one workshop accepted and was ready in two weeks. Years later, both the C6 and ETX105 are still in use by me. 

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I've had my C5 for the past 10 years and paid a mere sum of 80 euros with a manfrotto tripod and all accessories for the C5 including it's circa box and manual albeit the white version with short dovetail. Still a great scope for the moon and planets. My first ever scope was a meade etx70

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2 hours ago, Alien 13 said:

I dont think that they have invented a scope yet that isn't a series of compromises.

I think that sums it up, everything is a compromise in this game.

If you want say 8" of aperture with a slowish f ratio in a compact and light ota the SCT is up there as a contender.

If you change your parameters/preferences then something else will be winning.

Edited by Paz
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I had an 8" Newtonian on a manual EQ-5 equatorial mount. I did not like it, and I did not like not having the GoTo facility I enjoyed with my Mak.  I thought of getiing a GoTo upgrade or another mount with GoTo, but opted instead to get a used C8 SE, and I have never regretted this decision in the slightest.  The C8 SE is easier to set up, more pleasant to use with the eyepiece at the back of an alt-az mounted stubby OTA, and contrary to the comments made about SCTs it worked better than the Newtonian.

I also found the large depth of focus made it much easier to use devices such as a binoviewer or flip-mirror diagonal.  The Newtonian would only focus a planetary camera with the focuser right against the stop.

The only thing the Newtonian did better than the SCT was to give a nice bright view of the whole of the Perseus double cluster.

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Very interesting topic, I have a 6 inch newtonium and with this scope I have had my best views, I also have a Celestron 6se and the views of the moon are very good.

The most used scope is my Meade ETX 90 with a binoculars viewer this is really good so portable.

I really like to use binoculars mounted on a tripod these are a go anywhere option, all I use my kit for is for visual viewing with the moon being my favourite.

I look forward to seeing the various meteor showers  and use the cheapest and best instruments my eyes

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I do no imaging, so my perspective comes from that point.

I own refractors, dobs, SCTs, and one Mak (6-inch). I like using them all, and do, on different occasions. Each type has its own charm and utility.

Best view of Jupiter I ever had was through my C-Nine-Two-Five.

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I bought an SCT as my first scope as its compact size and weight was good for lugging to my darkish site on foot without sacrificing too much aperture.  The EQ5 mount held it well.  I did all of the Messier list with my C8 and a good start on the Herschel 400.  The SCT design though is a real pain for any amount of dew and freezing conditions rendering them virtually useless without a shield and a heater.  Cooling off the 8" size took an age although I didn't find that bothersome for DSOs it did give good planetary views when stable - stars though were never really brilliantly sharp especially when compared to my refractors.  Once I'd got into the Herschel list though the aperture obviously wasn't sufficient and replaced it with a 12" Dob.

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I bought a C11 because I wanted an affordable step up in aperture from my TEC140.  I also have a 12” f6 Newtonian which is great optically but more awkward; the C11 is stubby, convenient, portable and has the advantage over the Dob of working well on my AZEQ6 enabling easy goto and tracking. I also had ideas of doing some planetary imaging ... which, of course, I never got round to doing! The refractor is the scope I’d never give up because optically and mechanically it’s as good as it gets and it delivers special image quality.  I am a fussy observer and I was prepared to be underwhelmed by the SCT but, on the contrary, I’ve been favourably impressed especially on certain targets. Optically, it isn’t bad at all. Its greater aperture allows it to easily outperform the TEC on the Moon - a high contrast target, of course - resolving finer and showing more detail. It performs very well with the binoviewer, especially on the Moon, globs and many compact nebulae and will take high mags on subjects like these. Collimation is easy and holds very well. Some minor image shift is discernible from time to time on focusing but, with modest focus changes, I've not found this to merit the fuss that’s often made about it. Perhaps I’ve been lucky with my particular example.  I did fit the Baader Click-Lock back in place of the Celestron original, and that’s an improvement worth making I think. I use it with the Baader prisms. In a real world where 11” apos aren’t an option, the C11 fills the gap I wanted to fill and, in the event, performs better than I’d expected.

.

Edited by JTEC
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